It had been thought that virus caused only brief, mild or moderate symptoms in adult cattle, with much worse life-threatening effects in unborn cattle, sheep and goats.

But, according to a report in Farmers Weekly, Tim Bebbington, from Castle Vets in Launceston, said the impact of the disease was not restricted to abortions and deformed foetuses.

"Every now and again several cows seem to go down quickly, with decreased milk production, scouring, low productivity and poor fertility. There's no evidence of anything else wrong except Schmallenberg," he was reported as saying.

He urged caution, however, as it was possible that other problems were being incorrectly attributed to Schmallenberg virus.

His practice had recently tested 360 animals from 60 beef and dairy farms across Devon and Cornwall - and only 15 tested negative for the disease.

Mr Bebbington told Farmers Weekly he has also received many reports of Schmallenberg in early lambing flocks, but the true picture could be far worse as the disease was still non-notifiable, he added.

Symptoms were also varied, including ewes carrying vast amounts of fluid with dead lambs. "It's looking much worse than last year, but many farmers aren't reporting it because there's nothing they can do about it - it's not a notifiable disease."

The number of beef and dairy cows scanning barren had doubled since last year, to 18%, said Mr Bebbington, who admitted feeling "very nervous about the spring calving herds".

A vaccine to protect animals against Schmallenberg virus could not come soon enough, he told Farmers Weekly.

As reported in Country Smallholding, the virus has caused severe losses for early lambers. In our February issue we reported how farms and smallholdings have been hit across the country.

One North Lincolnshire smallholder said he had lost half his lambs. A Derbyshire farmer said he had lost 30 per cent of his.

* Leading pesticide manufacturer Agropharm Ltd is urging farmers and vets to take action before the virus affects their livestock.

Agropharm Ltd. says it has developed Neem Pro Riddance, an organic, water based, anti biting agent designed to control midge bites and limit the spread of the Schmallenberg Virus. It says Neem Pro Riddance is the only product on the market to actually prevent biting thereby protecting the animals from risk of contracting Schmallenberg. MORE: www.hygienesuppliesdirect.com